LISTing Newsletter

| LISTing Newsletter

Newsletter of the Long Island Sinclair/Timex Users Grou ET

v

September 1993 Issue

NEXT MEETING SEPT 12,1993

7 NACI So On
Mids ` TN. i Keps 7a

Listing Policy Annuai Dues...$ 16.00

One "sample" copy sent upon receipt of a large SASE.

Copies provided on EXCHANGE BASIS with other bona fide user groups.
Listing is published monthty except duty and August by LIST (tong
fsiand Sinclair Timex) Group, a non profit aser group.

We are aiways looking for articles, programs, reviews, etc. to keep

our members informed and entertained. You maintain fatt copyriabt.

Portions of this publication may be reproduced, without written
consent. Please give credit to LIST when reprinting our articies.

LIST disciaimes any responsibility for any damage you may do to
your Computer as a result of reading any articles in LIST ing.

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USERS

QL CORNER

Great news for QL Users! Psion, UK has declared XCHANGE, a suite of
four bundled programs, (Quill, Archive, Abacus and Easel) as public
domain software. All QL and QDOS users can freely distribute copies
among their groups for personal use. The version of XCHANGE being
distributed is 3.9% which was rewritten and produced by Dansoft for
the Thor computer (a QL in a PC case).

My understanding is that each of the five programs (Xchange, Quill,
Archive, Abacus and Easel) have the latest upgrade which include
additional commands.

The Xchange file is approximately 183K, which will only operate with

disk systems as the file is too long to be placed on a microdrive
cartridge.

Thanks to LIST member, Joe LaPunzina for providing me with a copy of
Xchange.

The diskette has many files on it, which includes a disk editor, a

file editor, a screen dump utility with many different printer
drivers and _doc files.

Xchange provides a multitasking environment, has commands of its own;
Set which allows the default data drive and Help file drive to be
changed; Output which controls printing a document as a background
task while you continue working on either of the four programs. TSL
is another command which stands for Task Sequencing Language. Seeing

this in action will astound you! There are a series of TSL files on
the disk.

My advice is to load Xchange. When the Xchange screen appears, press
CTRL/C, then F3, T. A prompt will appear on the command line; enter
TUTOR and then press enter. A menu will appear at the top of the
screen offering a tutorial for each of the Tasks (Quill, Archive,
Abacus and Easel). Press the appropriate letter for the task and
Xchange will load and run the tutorial file of your choice.

Quill has several new commands: Glossary which allows the user to
designate a character to be used as a 'Macro'. Export, which will
output the current file in memory to be printed to a file in ASCII,
without any control characters attached (except carriage return). In
other versions you could do the same thing when printing toa file
instead of printing to a printer. However, when you choose this
option the user had to remove the disk with the printer driver on it

so as not to have any printer control characters embedded within the
file.

There is a Mail Merge facility included within Quill and another
command called Extract, which operates much like the copy command but
will allow you to save blocks of text to a disk so that they may be
merged into other documents.

If I have interested you in the Xchange suite, you can send mea
formatted 726K disk (either 5 1/4" or 3 1/2" diskettte), with return
postage (normally 75 cents for one disk) and encolsed in a decent
envelope which can be used for the return mail, I will copy the
entire disk for you and mail it back to you. I have a disk with the
Xchange HELP files formatted into _doc files which makes life a lot
easier when printed out on paper instead of reading the Help files on
a screen. If you want these files include an additional formatted

720K disk - the postage for both disks usually runs at 99 cents.
See you next month....Bob Gilder

THE TITER EMULATOR FROM HELL by John Pazmino

Sy now the supplies and sources for Sinclair hardware are quite
dwindling. It is tough to introduce newcomers to Sinclair for the
general lack of apparatus to outfit them with. On top of this is the
pervasion of the IBM type of computer among the vulgate which works
fiercely against adopting Sinclair as a new platform.

What to do? In the UK, where Sinclair still rules in the 8-bit
computer world, there were efforts to work a software solution: Turn
the IBM into a Sinclair. In principle this is easy because the Z80 CPU
architecture has been emulated on the 8088 (and higher) chips thru
software. Many readers will remember, and perhaps still have, the CP/M
emulators on the early IBM rigs.

However, emulators for the Sinclair have been, well, ech!. Why?
Mainly they are written by Sinclair folk who on the whole are unversed
in IBM. In deed, some Sinclair emulators are nothing but the Z80 code
of the Sinclair ROM shoved into a Z80 CPU emulator. This was for many
years not cricket becasue the code was the proparty of Sinclair and
then Amstrad.

There's a physical barrier, too. Except for the very first IBM PC,
issuing simulataneoulsy with the Sinclair ZX-81, the IBM has no innate
means of receiving input from a cassette. Some emulators Simply gave
up at this obstacle and work only with type-in programs.

Well, now in this merry year of 1993 comes the Killer Emulator
from Hell, a Sinclair emulator for the IBM that does everything a
Sinclair emulator should do and does it right. This new emulator, Z80
iS a shareware creation from Europe.

Shareware, not lucreware.

This point is crucial. For in early 1993 Amstrad, who holds the
rights for the Spectrum and QL, formally threw the code for the ROMs
into public use. That is, anyone may now copy and distribute the
original ROM code in their own products PROVIDED that these products
are noncommercial. Commercial use of the ROM code is still prohibited.
Ergo, altho Z280 does have woven into it native Sinclair code it is
copasetic and quite kosher.

Z80 dissolves the above -- and many many other -- problems in
bringing the Sinclair to the IBM. It comes on an IBM stiffy with 720K
of files. They rehydrate to about 2M on your harddisc. Two megabytes!
That's, um, more than thirty Spectrumsful! What ARE all these crazy
files!? Relax, already. Most of the files are sourcecode and

r

leaving 'just' 330K of working files. That's STILL about five
Spectrumsful of stuff. For emulating a Spectrum?

They toto in uno are a symphony of several Sinclair systems: the
Spectrum 48K model, 128K model (with pixel graphics and multichannel
sound), Interface 1 (with serial ports), Sinclair and Kempston
joysticks, Multiface 1 (with memory capture), tape loading indicator,
280 dissembler and monitor, header-reader, screen editor, RAMdisc,
swoppable ROMs, Microdrives, Disciple discs, and (of course!)
tapedrive. All of these are provided via software in quite perfect
replication of the original hardware gadgets. Thus, the complete
inability to attach native Sinclair accessories to the IBM is much
overcome by building the most crucial ones right into the emulator.

The emulator receives its original input from cassette only. This
requires a cable connecting the IBM parallel port to the cassette
deck, with some circuit bits along the way. The emulator has clear
instructions for making this cable and it took me an afternoon to
build it, including a stopoff on Canal Street to get the parts.

If you in giddy delirium shoved Z80's disc into your IBM without

r

making the connector, chill out! Z80 comes with seven ready-to-run
Spectrum programs. Nothing fancy, some games and utilities.

I can not here elaborate on the very many details of this
emulator. That would amount to describing the entire Spectrum world! I
here highlight a few major features. This emulator, for starts, in
fact does what every Sinclair fan sweats in sleep for: IT BODILY
TRANSFERS TAPES TO DISC. Yes, it takes the files from tape and mirrors
them on a regular IBM file. And this file to the emulated Spéctrum
quacks and flies and waddles exactly like the original tape. The major
positive(!) difference is that you never 'spot' or 'rewind'. This
feature alone virtually eliminates the 'tape loading error' from a
tapefile that failed to catch. It'll pass around again in, oh, a
millisecond for another go. Each 360K disc holds several, depending on
length, cassettes of programs.

With Z80 you may choose between a replica of a cassette OR AN
ORDINARY IBM FILE. That is, you may load from EITHER the emulated tape
OR from an IBM file that contains the program in DOS form! Hand up?
Yes? Sure, Z80 converts the one kind into the other!

You over there? Voce alta, de favore. OK, you have several short
tapes Or programs and you want to combine them on one cassette. What a
magilla on the real Sinclair! Load from one tape; swop tapes; spot it;
Save to it. Swop for the next tape ... . With Z80 you merely knit
together the separate 'tapes' in any order you want and get one
consolidated new 'tape'. Yes, that right. Uh, let's continue, please?

These grand goodies so far are alone enough to justify the
nuisance of reaching overseas for this emulator. In one weekend you
can put your entire Spectrum collection onto disc WITH ABSOLUTELY NO
MODIFICATION OF THE ORIGINAL CODE. You 'bung the tape' by specifying
the tape's IBM file, do a LOAD and the 'tape' goes ahead and loads.

Please do understand that this is utterly NOT a "RAMdump', ‘memory
capture’ or 'snapshot'. Z80 does this, too, as an altogether separate
function. In the tape mirror each file of the tape is actually in the
IBM file and you even use the (included!) header-reader to see them.
What's more, the header-reader browses the tape and loads ANY tape
file you want. You don't have to let the tape run thru to load the
program way off at the tail end. Hmmm, a random-access cassette tape.

The Spectrum keyboard is exactly mapped to the IBM keyboard. You
use all the keywords and tokens. Being that the IBM has no Sinclair
keytops, you popup a Sinclair keyboard diagram. It's really a rather
faithful depiction of the chicklet Spectrum with the corner colorband
and all that. There is no such mapping for the Spectrum 128K becuase
this model does not use keywords and tokens. You type in everything
litteratim with all the regular IBM keys.

Besides the replicated Spectrum keys, the extra IBM keys are
energized. You, for instance, get the <=> symbol by <sym<L>> or by
just punching the <=> key. Either the IBM <alt> or <ctl> keys stands
for the Sinclair <sym> key. I do see a danger in this convenience!
Play with the Spectrum-in-IBM for a while. Then go back to the real
Spectrum. Where the eff is that <[> symbol!7?

The numberpad is the cursorpad, the Sinclair joystick, or the
Kempston joystick -- as you wish by selection. The cursorkeys work,
too, for editing the command line. <esc> is the EDIT key, as is
<sft<1>>; <bsp> and <del> do DELETE along with <sft<0>>:

The IBM functionkeys are the adit to the emulator's forest of
functions, with <Fl> being the general 'help'’ feature and <alt<Fl>>
popping up the Spectrum keyboard layout.

When you do a screensave ("SAVE <name> SCREEN$"), THE SCREEN$ FILE
CAN BE SHARED WITH OTHER IBM PROGRAMS. What?! Uh, you see, this
emulator converts a Spectrum SCREEN$ file into a GIF or PCX file!

You share textfiles, too, with other IBM programs by a conversion

`

between Sinclair's CR-only and IBM's CR/LF line terminations. All
these conversion use the IBM file as the working medium.

The Microdrives are mimicked on IBM file. There are eight
"microdrives' in the emulator, the maximum capacity of the original
Interface, and each ‘cartridge' is an IBM file. You 'slot' a
microdrive by allocating a file to a drive. Ah!, to use a new
cartridge you must 'format' it ("FORMAT "m";3;<name>"; hey!, .those
extra IBM keys ARE cool!). This creates a new IBM file 137K long with
126K of 'tape'. Two of these fit on a 360K floppy or five on a 720K
stiffy. Once you format a emulated cartridge you can work with it
exactly as you would a physical cartridge. You even pull a 'catalog'
of the file and 'erase' stuff from it!

The Disciple disc is, too, cloned in Z80, altho the United States
never enjoyed this system. Again, the IBM file is the working medium.
Being that on stateside we deal with many minor disc systems, can 280
handle, say the Zebra system? Now comes the freako part. The code for
the Disciple system is excisible from the primum corpus of the
emulator. YOU CAN REPLACE IT WITH THE OPERATIONS OF YOUR PECULIAR DISC
SYSTEM. Yes!, you may ultimately junk the hardware of the Zebra system
and run everything from the Zebra code you wrote into 280.

The total supplantation of Sinclair's physical media with IBM
files lets you jettison just about every disc and cartridge utility in
Sight. With your stuff in IBM files you can apply any and all of the
IBM file utilities on it. Farewell, Cartridge Doctor! Vale, KopyKat!

Wait a minute!!! What happens to all those luscious Sinclair
cartridges and discs in those milkcrates? Since you Simply can not
feed them to the IBM you must revert to the original tapes. Load the
files into Z80 from the tapes and save them onto the emulated disc or
cartridge. WIthout such prime tapes you may have one revolting job
before you! You must transfer the disc or cartridge files back to
cassettes and then procede as just described.

Communications thru the emulator use the cloned serial ports of
the Interface 1. Remember my series a year back on PostScript on the
Sinclair? (Yesyesyes, I know, LISTings missed out the fourth and final
part.) Now you can actualize this by running 280 on an IBM fitted with
a PostScript printer. But there's a weirder prospect, attainable with
280: Pass data from the Spectrum to an other IBM program. You in this
case do not need a PostScript printer; use your existing printer! You
run a PostScript software emulator like Emulaser or GhostScript on the
IBM and send Spectrum generated PostScript files to it. Ugh! such
disgustingly gorgeous output. From a Spectrum. FROM A SPECTRUM!

Pecuase the emulator is European the presumption is that you use
the serial port for printing and the instructions detail conversing
with a printer thru it. In the US printers are routinely hung from the
parallel port and the serial port is the avenue to a modem. Hence, in
making the cassette cable, include a 'Y' connector or A-B switch so
the printer and cassette can coexist. To accommodate the possibility
of a parallel printer, Z80 allows a redirection of output to LPTx.

However, there is a clumsiness in using the printer, one of the
[very] few downpoints of Z80. The LPRINT, LLIST, and COPY commands do
not fire characters directly to the attached printer. You have to
first open a channel to the printer ("OPEN #3,"t"") and then send
output to that channel. I already wrote, via Internet, to the author
about this and suggested that he make LPRINT, LLIST, and COPY send
output to a DOS printer driver of the sort included with word
processors. If he can work this into a future edition of Z80 you'll be
printing to whatever device you got attached to the IBM.

What the deal about other ROMs? You recall that the American
flavor of SPectrum, the Timex 2000, has a dockport into which an
external ROM plugged to override the onboard ROM. Also, when the Zebra

=

disc system is fitted to the Timex, its own ROM is paged in when a
disc command is issued. Well, you can set up a battery of ROM files
and let the emulator bank off of them (one at a time).

How? There are two methods. The first is to get the ROM code into
an IBM file and then point Z80 at it when igniting the emulator. This
bypasses the default ROM file. The other is to patch [a copy of] the
default ROM file with code for the new ROM and let 280 go and .think
it's drinking up the same old code.

By now your throat is dry, your glands are leaking, your hairs are
dropping out. TELL ME, UNCLE! , UNCLE!, WHERE IS THIS Z80 THINGIE!!
Send off 15 British pounds to B G Services, 64 Roebuck Road,
Chessington, Surrey KT9-iJX, England and ask for the Z80 Spectrum
emulator for IBM computers. I did this and got my emulator in 12 days
flat. To pay from the US I just took my ordinary check and wrote it
out for "fifteen British pounds" payable to "B G Services"; it went
thru smoothly. Plastic is not [yet?] accepted. B G Services is a
Spectrum outlet and it'll enclose a sheet for its other items, too.

k ke he l b Bee eS E E - A ai h t= 128 28

MAY
/

1 REMXXXXXXXXXXXXXXXXXXXXXX
10LET1=16427 15INPUTAS
20 IF AS="S" THEN STOP
30 PRINT AS: “**";

40 POKE 1, 16*(CODE (AS)- 28)+ CODE
(TLS(AS))-28
50 LET 1=14 1
60GOTO 15

80, which is something of a

rarity. The REM in line one
must contain more characters than
there are bytes in the machine code
program. The number code 118 must
not be used in machine code routines
or all kinds of strange things will
start to happen to the listing.

To remove the REM statement
from line one, POKE 16403. 10. This
program will help many people who
still own a ZX-80 to obtain more
power from it using machine code.
Machine code programming is
something which has not been enter-
ed into any great depth with the
ZX-80.

| | EXLOADER works on the ZX-

ER TARGET
PAIN ARAS DI

P.J. Donnelly

a 1984 MICROSOFT BASIC

v

HARDWARE REVI EW

LU map HELLU

nima S SA a
ZO LFRINT MIDS ASTID)

IT: ROMPACK 30 LFRINT l EFT (A3. D)
USE: INSTANT LOAD SOFTWARE 40 “TNT Sr S046. 77
FOR: BK/?K RAM |
FROM: ROMPAK, INC. Æ Æ
SUITE 100, 8206 BLACKBURN AVENUE HE
LOS ANGELES, CA 90048
PRICE: $9.95 KIT, $16.95 A & T WITH ZIF + $2.00 P&H Lt
At $9.95 I just couldn't resist ROMPACK's basic cartridge kit for
SINCLAIR BASIC
4 and 8K EPROMS. The thought of instant loading software was just too much.
Of course, the ROMPACK is of little use on its own, so I also broke down and
bought che $9.95 Galactic PAK test game.
The ROMPAK is a small (3” X 3") open, double-sided printed circuit =e 3.2 TI 2)
board which plugs onto your ZX/TS expansion bus. A aaie bus extension pro- 13 5 = ee oats =ø

trudes out the back, s0 you can atrach aor periphērais (like a KAM Pack).

The board is uncased and in this stripped version has a transistor for control

of EROS, an 15138 selector for decoding. and a socket for 24 pin or 28 pin ae

EPROMS. The more advanced version has a Zero Insertion Force (ZIF) socket

which is probably a aust if you plan co use more than one PAK. (ZIF sockets

have a special mechanical construction, using a lever, which eliminates the

wiggling and pin bending problems, which often accompany [.C. removal/ insertioa). NOTE: Liwes 20 & 30 are reversed.

No extra power supply is needed. You aust use a 16K ram pack with ROMPACK, as

the programs are apparently booted up into the BASIC area for execution. You

do this with a RND USR command and are instantly into che software. One Rinor

inconvenience, in the case of Calactic PAK, was that once booted to BASIC, che

program can’t be SAVED. It's easy enough to get around this (an LDIR to and

froe a long SREM statement), but for those who like to experiment, a bit of a —

hassie. Yer

JEAEPEEERPER,

“DEERE |

BOMPAK' s decoding scheme ís a litrle strange, allowing easy use of the
8-16K area (A 13 high pulls RAMCS high through a transistor), but not such easy
use of other & blocks. This was apparently done to Simplify crace layout, but

makes it sommwhat inconvenient to use. In any event, I don't recommend trying
to asp into other areas without a complete schematic. The instructions with ROM-

PAK indicata you can use other 8K blocks,and jumper pads are even supplied. But,
ao provision is made for ROMCS whem other blocks are used (e.g., it's a simple _

task to install your owa system ROM in the 0-8 block. With che decoding of ROMCS
as is, howevergboch your ROM and the Sinclair ROM would be enabled at the

Copyright 1984
Donnelly

P.J.

same time unless you further decode the 138's output).

SINCLAIR BASIC
AS(LEN(AS)=1 To)

AS(3 to 4)
AS(to 2)

My "kit" came already assembled and for $9.95 I give che ROMPAK a
9 out of 10, based on price. Compared to TIMEX's 1510 module, ROMPAK lacks
sows features (e.g., RESET button and attractive case) but, the ease of access

g some Microsoft) BASIC
He offers the following

to the address lines helps co maka up for this. I see ROMPAK as a very viable

low cost EPROM holder for dedicated tasks. An example would be for a Solar Hot `

Water control station. You could design your system control using say a Byte

Back 38-1 module, ROMPACK and 16K RAM (possibly even just che 2K). A RAND USR

would be all you'd need to gec Ít up and running - No tapes or recorder wires

to worry about; even che TV set could be despensed with if you had an LED to

show that the sofrvare booted OK. Such a software system could be developed on |

RESULTS

2)

ë Hunter Board, for example, and then transferred to EPROM. Dre weasems ieir ~ Sama

sample correlation for STRING handling.

Marty J., has been enterin
Programs into his 2068.

MIDS(AS,3,2,)
LEFTS (AS, 2)

MISCROSOFT
RIGHTS (AS

While I didn't chink much of the Calactic PAK software (a very simple
“no ve through space" game), che ROMPAK hardware is simple, elegant and inexspen-
sive and represents a good buy for the hardware experimentar.

mr
1

€ 419848
P.J. fonmeile

Centerport, wi...

HARDWARE REVIEW

ITEM: 1510 COMMAND CARTRIDCE PLAYER
USE: INSTANT LOAD SOFTWARE
FOR: 8K ROM/16K RAM
FROM: TIMEX CORP.
WATERBURY, CONN. 06725
PRICE: $19.95 + PAH ($2.50)

The prices of che promised software for the 1510 are only slightly
higher than chetr tape counterparts, so spending $20 for the convenience of
instaat loading seems a small price to pay. Of course, as usual, it's been
over two months since [ ordered software and while | received the player
quickly my cartridge arrived oniy yesterday. What can you do vith just the
player, I thought? First, leta have a look at the hardware.

The TS 1510 ís a small (3” square by 2 1/2" high) silver plastic bor,
color matched to the 2068 (on which it probably will not vork). A female edge
connector mates to the back of your TS or other peripherals and an erpanasioa
bus extends ouct the rear for your l6K RAM. 1⁄4 coatact cartridges are inserted
from the top into another slotted card edge connector. The unit needs œo

auxillary power servica,sad you suse havs 16K to use ir virh a cartridge.

Under the hood of the 1510 ís a double-sided Printed Circuit Board
with pla ced through holes (DSPT). Components include chip-select logic consist-
ing of a 74LS02,quad NOR, 74LS00, quad NAND, some despiking and filter capacitors,
and a simple pull up resistor and diode OR (sometimes called Mickey Mouse logic)
for ROMS. (Preliminary schematic attached). Do look over the schematic care-
fully before you use the 1510 with non-TIMEX peripherais, as the decoding is æt
quite complete (i.e., there is nothing above 32K, right?). Also inside the i510.
meunced just under the front female edge connector, is a small strip of spring
steel supported by a foam rubber pad. This little add-on greatly increases stav-
(itty and virtually eliminates “RAM PACK WOBBLE” type problems for che 1510. Te
inside of the case is spray metallized to reduce RFI. Since the socket coanector
pias are only about 3/32” above that metal coating, ['m a little worried about
pushing down too hard on a cartridge and causing a problem. But, as pover is
supposed to be off when you do this, it should not materialize for most.

A word of caution though, om the back (male) edge connector, the
solutiona to “wobble” vas apparently to make the slot extra tight. Mine vas
too tight, ít pulled tha kay out of ay RAMPACK, and broke some plastic out as
well. I almost lost the RAM pack the next time [ used ic, as the key vas
@issing.

Besides increased stability, the 1510 has two other features that
may make it a good buy, for many, even withouc cartridges. These are: 1) A
RESET awitch. You can simply leave the 1510 hooked up all che time and obtain
4 warrantee saving, simple-co-use, RESET function. 2) Bus extensica. Any
aumber of peripherals have comoqnents ericking cus which provence disect sount-
ing on tha back of the TIMEX. Bus extenders cost from $12 to $20 and in many
cases could be replaced by the 1510.

I had been using my 1510 as a RESET box oniy weil I received ay (irst
software cartridge, PSION’s FLICHT SIMULATOR. I'm sure that program has been
reviewed elsewhere so we'll cover just five points of using the cartridges.

The Timex cartridges come attractively packaged in a card box and are
about 2 1/2" square and only 1/8” thick. They can oniy be inserted coe vay acd
Cake a considerable amount of force to insert. The gold edged contacts are pro-
tected while not taserted in the player by a self recracting plastic sleere.
Interestingly, instructions for the: 1560 only vere supplied with the cartridge.
They indicate that it vill come up Tunming om that machine. Oa TS 1000's, you
wust execute a AND USE 8192 to a ML routine in the cartridge's EPROM. That, in
turn. boots ths ML and BASIC program up into the 16-WK arsa for axucution.
You can modify the program-sad even “SAVE” it then, {ros BASIC. Do note chat you
could diseassemle TIMEX’s transfer routine and use it with, say, a Hunter board
to produce your owa “instant” software. However, only an SK or less programs

(mot includiag variables) can be stored and transferred.

The 1510 is a good valvue for the money (a 9 out of 10 on æv scale)
even as a stand alone peripheral and seems to be an excellent and econowmicial

`
way to use software. Lets hope Timex reproduces all their titles om cartridge.
`

t

BOMBING
MISSION

OU SIT tensely in the seat of

y your cockpit, staring anxiously
through your viewfinder at

the ground. Your mission is to find
and destroy the enemy munitions
dump-as quickly as possible. Your
finger stabs at the key with the
downward arrow marked on it and
the bomb is released. The game runs
on the 1K ZX-81; as the aircraft
crosses the sky you must release
your bomb using the 6 key to bomb
the target on the ground marked
with a graphic A. The target will

appear randomly on each run.
Graphics notes:

Line 30, graphic S.

Line 70, graphics T, Y, T, 6, 2 '—',
inverse space, graphic 6, /, space, 21
graphic Ts, inverse space.

Line 120, graphic T, 6, T, 8, space,
graphic T.

Line 210 graphics graphics Y, 8,
space, graphic T.

1Ø LET A=SGN PI

28 LET S=A-A

38 LET G=CODE “GRAPHIC S"

40 LET F=INT (RND¥(G+G)>+CODE
"ge"

50 LET 2=A-A

68 LET X=A

78 PRINT AT G.A-As"TYTE- 67 TT
TITTTTTTTTTTTTTTTTT "

80 PRINT AT G.FiCHR® G

98 PAUSE (GxG>

100 FOR B=A-A TO CODE "Ø"

120 PRINT AT ALBsCHR® (A-ADs "TE
T8 T"

130 IF INKEY$="6" THEN LET Z=A
149 IF Z=A THEN LET X=X+A

150 IF Z=A THEN PRINT AT X,B+A;
160 IF ¥=G THEN LET Z=A-R

172 IF X=G AND B+A=F THEN GOTO
CODE "ABS"

188 NEXT B

198~LET S=5+A

200 GOTO CODE "W"

218 PRINT AT G-A. F- A-A); "YBOOM
T"JAT G-<(A+A>),F-AJ "Y8 T") TAB GIS
+" BOMB"+¢"S" AND S>AD

POKE 16418,Ø
130 PRINT AT 23,0; "TYPE C TOR

TY UN,Z TO COPY DESIGN"

W 14Ø IF INKEYS="" THEN GOTO 140
RY 150 IF INKEY%="Z" THEN GOTO 188
Wi 168 IF INKEY%="C" THEN RUN
/

172 GOTO 148
180~PRINT AT 23,8;"¢€32 SPACES)"
192 COPY

288 GOTO 138

HE AUTHOR of Kaleidoscope,
Matthew Calveley, of Lytham,
Lancs, claims amazing results
with this ZX-81 program. It will
generate a random number of dots at

N®INT © RND*250 +288
, Ami TO WN

VæINT (RNDX22 >
H=INT í RNDXS32 >
RY=21+ 22-7 )
RH#31+¢ 32-H >

H.V

RH. V
RH. RY
H. RY

random points on the bottom left of
the screen and then re-create that
pattern on the other quarters of the
screen. All the patterns created will
be symmetrical.

Kaleidoscope occupies 1.2K of
memory but can be squeezed into 1K
by removing lines 120 onwards,

using VAL where numbers are used
and by changing line 10 to:
10 LET N=INT (RND*25)+25.

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